The Gunners have been handed a massive injury boost ahead of the big clash with Tottenham Hotspur in the League Cup on Wednesday evening.
Arsenal saw their long unbeaten run in all competitions come to an end on Sunday as a late header from Charlie Austin handed Southampton a surprise 3-2 win in the Premier League.
The defeat was not expected by most fans even though Unai Emery went into the clash without two of his key defenders.
Missing against Southampton was Shkodran Mustafi, who has been one of the regular names on the team sheet so far this season.
The German star was suspended anyway but he has been sidelined by a worrying hamstring problem which he picked up earlier in the week.
Ahead of the clash with Tottenham Hotspur though, Mustafi has resumed training with the first team.
The defender’s return to action is a major boost for an Arsenal defence which has been hit by several injury blows this year.
Mustafi took part in Tuesday morning’s training session at London Colney as he looks to make a return for the Gunners who desperately had midfielder Granit Xhaka playing at centre-back on Sunday.